Hi there,
I was in the Hancocks store in Tucson yesterday and saw the little stick on thimble dots. they are designed to be used on the left hand that goes under the quilt to keep from sticking your fingers. Don't know what they are called but don't see why you couldn't use them on your thimble finger to. I am going to try them because I have a callus on my thimble finger too.
Jane Sisk
Tucson, AZ